Set-protector for drilling.



J. W. REASON.

SET PROTECTOR FOR DRILLlNG.

APPLICATION E 1, 1 48,537. Patented Aug. 3, 1915.

INVENTOR BY ATTORN EY JOHN WILLIAM REASON, OF GRANITEVILLE, VERMONT.

SET-PROTECTOR FOR DRILLING.

Specification of Letters Patent.

Patented Aug. 3, 1915.

Application filed February 1, 1915. Serial No. 5,516.

To all whom it may concern:

Be it known that I, Join: WV. Reason, a citizen of the United States, residing at Graniteville, in the county of Vashington and State of Vermont, have invented a new and useful Set-Protector for Drilling, of which the following is a specification.

This invention has reference to set protectors for drilling, and is designed particularly for use when cutting cores in deep channeling in order to maintain the set on the core and preventing it from jumping off.

In deep channeling it is customary to bore a row of holes each separated from its fellows by a wall customarilytermed a core, which must be'broken away in order to produce a continuous channel. The bores sometimes reach as much as twenty feet in depth and difliculty is experienced in keeping the tool used to cut away the core, and usually termed a set,'from jumping away from the core. By the present invention there is provided a guide for the set which is movable up and down within the bores, and may follow the set, holding it in proper relation to the core being treated until the latter is ultimately cut away, whereupon the guide isremoved from the particular bore :in which it travels, and is advanced to the next one to there guide the set in eliminating the next core in order, and so on throughout the series of bores defining the channel.

The invention will be best understood from a consideration of the following detailed description, taken in connection with the accompanying drawings forming a part of this specification, with the further un- .derstanding that while the drawings show a practical form of the inyention, the latter is not confined to any strict conformity wlth the showing of the drawings, but may be changed and modified so long as such changes and modifications mark no material departure from the salient features of the invention.

In the drawings :-Figure 1 is a longitudinal section of a series of bores showing the guide in operative position. Fig. 2 is a section through the bore occupied by the guide, and taken at right angles to the section of Fig. 1. Fig. 3 is a horizontal cross section of the series of bores of Fig. 1, taken above the guide. Fig. 4 is aperspective view In drilling in hard stone it is not uncommen that the drill holes taper more 'or less from the .top to the bottom due to the wearing away and resharpening of the drills, but this feature has nothing particularly to do with the present invention.

In the drawings there is shown a series of closely adjacent bores I assumed to be formed in rock, such as granite, preliminary to connecting these bores to form a continuous channel, so that a block of granite is readily broken away from its position in the quarry. These bores often reach a considerable depth, which may amount to as much as twenty feet, and between the bores there remain walls 2, since the bores do not coalesce, and these walls are ordinarily termed cores. In order to produce a continuous channel the cores must be eliminated. Ordinarily a tool called a set is employed for the purpose of cutting away the cores, but great difliculty is experienced in keeping the set to the work and preventing it from moving from the core into one bore or the other. \Vhile this difficulty is not experienced in the first few feet to any great extent, it increases rapidly as the bores deepen, so that it becomes very difficult with deep bores.

In order to provide a simple and yet very eflicient means for guiding the set in the operation of eliminating the cores, the present invention comprises a block 3 preferably of general cylindrical form, and of somewhat less diameter than the bore. This block has a radial tail portion 4 which may be somewhat elongated in the direction of the length of the axis of the cylindrical block or head, and is of a width permitting it to extend through the channel produced by the elimination of the core between two adjacent bores. That portion of the body 3 remote from the tail 4 is flattened as shown at 5 and this flattening may be in chord relation to the cylindrical head and parallel with and quite close to a diameter extending transversel to the longitudinal center line of the tai An eye 6 at about the center of balance of the device provides means for the attachment of a chain 7 or other suitable strand, whereby the guide may be raised or lowered in the bores.

Considering the bores as progressing from the one shown at the left hand end of Fig. 1 toward the right, it is customary to eliminate the core between the first and second bores by hand without the use of the guide. This provides a space for the tail 4 to travel with the head 3 inthe next bore in order.

The face 5 is presented toward the next core and serves as an abutment for the set to bear against, thereby holding it in position tacontinually engage the core being cut as is eliminated to the desired depth. Thenthe guide is raised and moved tothe next bore in order and the cutting of the following core proceeds as before. The operation is repeated until all the cores have been eliminated, and then theblock is separated from its bed inthe usual manner.

The guide has the advantage of extreme simplicity of construction with the tail & working in the ace formed by the elimination of the preceding core, and, furthermore,' the guide, is capable of extreme mobility and performs its function without regard to the depth of the bores. The guide is a relatively small device with the head one and one-half to two inches in diameter for a three and one-half inch bore, while the tail need not exceed three to three and one-half inches in length, and the height of the device may be four or five inches.

Such a device will readily work in a bore averaging three and one-half inches at the top and two and one-half inches at the bottom when the bore is as long as twenty feet.

' What is claimed is 1. A free guide for a core removing tool used in producing channels in rock, consisting solely of a member having a head portion adapted for side engagement with the tool, and a tail portion extending from the head portion and of such thickness as to readily traverse the space caused by the removal of the core between two adjacent bores, the head portion being of a diameter to move along a bore and of greater diameter than the tail.

2. A free guide for a core removing tool used in rock channeling, consisting solely of a block formed into an elongated head approximating in diameter that of the bores produced in the rock and adapted for side engagement with the channeling tool, and

a tail extending from one sidev of the head and of a thickness and length to readily pass through the space produced by the re- ;moval of the core between adjacent bores, said guide being provided with suspending means individual thereto for lowering it into and raisin it from the bore.

3. A free guide for the tool used in removing cores between adjacent bores inrock channeling, consisting solely of a block formed into a cylindrical head with one side flattened in chord relation to the head for abutting one side of the channeling tool,

means for the guide individual thereto,

whereby said guide may be lowered into and raised from the bore with the tail extending through the space produced by the re- JOHN WILLIAM REASON.

\Vitnesses THEODORE LASCOR, BERNICE Wmnun. 

